You know how in the end of NSMBW, blocks show up that say the names of the
creators of the game? You can edit that with this. You need to edit the text file first.
You then use the encode option to put all your edits together.

In Newer, each world has it's own course name,
world name, course id, and much more. This can edit what the course
is called, what the world is called, how many worlds there are, what
world map file to open, decide whether the world is divided into to 2
or not, decide if a course has a secret exit or not, and much much more.

Well, for Reggie, you should just use Reggie Next made by MasterVermilli0n, found on his Github

Old 3DS XL info:
I used to have a 3DSafe A9LH V11.3.0-36U with Luma in my CTRNAND. Since ReiNAND Reibooted and Re-Reileased, I "switch"ed back.
Right now, I have boot9strap with Luma 8.0 as my CFW. Though, I'd like to see other CFW's for B9S.